Changes to Docker-related files/configuration don't occur in a vacuum.
They are made in coordination with changes to the main repository, so it
doesn't make sense to track them separately.
Note: Removing the 'windows' Docker files completely. No one has has
used them in a long, long time. The client build would be broken in
there anyways, the image is based on .NET Framework 3.5!
Can't recall why 'deribit-crypto-connector-demo-application' was added as a
submodule in the first place. It has no actual corresponding files in the main
repository, just an entry in the '.gitmodules' file. Removing it now because
it's causing jenkins builds to fail (jenkins attempts to clone all submodules
in the .gitmodules file, and it doesn't have access permission on this one).